Attributes disappear when exporting to Excel & web

Hello,
I bought Excel-like Product Manager yesterday, and it doesn't work well, unfortunately.
Hopefully, I'm doing something wrong..

1. When I export my products to Excel I've noticed that some product attributes (that are visible in the web version) are empty in Excel.

What's very weird, the attribute column is there, and some other products have this attribute created correctly. Just some are missing.

Please help.
I've checked if my server is not overloaded while exporting - it's not.

2. When editing products in the web version my variable products get destroyed - although I'm not tuching variations. I'm sort products by the "Product Type" column and edit some attributes of "Simple" and "Variable" products (not changing rows without a name - those are variation, right?) Am I doing something wrong?

Please help

Thank you.

Marta

ps. I've just noticed that the attributes that don't appear in excel were imported in bulk via other importer. When I remove this attribute from product and then add it again by hand your exporter sees it in Excel. WooCommerce sees those attributes perfectly fine, so there must be something that your exporter doesn't read. Please help, because I'm stuck, and I have hundreds of products, so it's not possible to edit them all by hand.

Thank you:)